The booting process of Windows Vista and later versions differ from the startup process part of previous versions of Windows. In this article, unless otherwise specified, what is said about Windows Vista also applies to all later NT operating systems. For Windows Vista, the boot sector or UEFI loads the Windows Boot Manager (a file named BOOTMGR on either the system or the boot partition), accesses the Boot Configuration Data store and uses the information to load the operating system. Then, the BCD invokes the boot loader and in turn proceeds to initiate the Windows kernel. Initialization at this point proceeds similarly to previous Windows NT versions. History Windows Vista introduces a complete overhaul of the Windows operating system loader architecture. The earliest known reference to this revised architecture is included within PowerPoint slides distributed by Microsoft during the Windows Hardware Engineering Conference of 2004 when the operating system was codenamed "Longhorn." This documentation mentions that the Windows operating system loader would be undergoing a significant restructuring in order to support EFI and to "do some major overhaul of legacy code." The new boot architecture completely replaces the NTLDR architecture used in previous versions of Windows NT. Most of the steps that follow the NT kernel being loaded, including kernel initialization and user-space initialization, are kept the same as in earlier NT systems. Refactoring in Winlogon resulted in GINA being completely replaced by Credential Providers and graphical components in Windows Vista and later. Boot Configuration Data Boot Configuration Data (BCD) is a firmware-independent database for boot-time configuration data. It is used by Microsoft's new Windows Boot Manager and replaces the boot.ini that was used by NTLDR. Boot Configuration Data is stored in a data file that has the same format as Windows Registry hives and is eventually mounted at registry key (with restricted permissions). For UEFI boot, the file is located at /EFI/Microsoft/Boot/BCD on the EFI System Partition. For traditional BIOS boot, the file is at /boot/BCD on the active partition. Boot Configuration Data may be altered using a command-line tool (bcdedit.exe), using the Registry Editor (regedit.exe), using Windows Management Instrumentation, or with third-party tools such as EasyBCD, BOOTICE, or Visual BCD Editor. Boot Configuration Data contain the menu entries that are presented by the Windows Boot Manager, just as contained the menu entries that were presented by NTLDR. These menu entries can include: Options to boot Windows Vista and